COOLING WITH COMPRESSED AIR

Focus

The Ranque-Hilsch tube, better known in industrial applications as the Vortex tube, is a device that separates the compressed air into two distinct streams, the first has a positive delta and the second a negative delta compared to the main input flow. The phenomenon behind the Vortex tube, despite having been widely observed and used in a variety of applications (mainly industry, aviation and meteorology) has not yet been fully explained by physics. A pressurised air stream is injected tangentially into a swirl chamber connected to two tubes of a suitable dimension. One of the tubes has an output regulated by a valve and starts to swirl which causes the part closest to the surface of the tube to heat up and the part furthest away to cool down. The two streams go in different directions and the delta can be adjusted by regulating the valve on the hose output which expels hot air. It is a question of cold ratio since the delta t generated is inversely proportional to the volume of the stream of air. The temperature differences which can be generated are significant, ranging from -40°C to 60°C, compared to the initial temperature of the air flow on input.

In aviation, the phenomenon is studied because it tends to occur on aeroplane wings in flight with the risk of causing dangerous accumulations of ice. In meteorology, it is thought to be responsible for the formation of hail under particular conditions of currents at high altitude.

In industry, Vortex tubes have long been used in a variety of applications in which they provide an important added value. They are particularly effective given performance and have the advantage of being extremely simple to implement (once they are connected to the compressed air, they start to work immediately and only have to be correctly attached and oriented). They have no moving parts (no maintenance is required) and they do no use electricity so are especially suited to places at risk of explosions or in damp areas. If the application allows their use, they are very convenient as they are cheaper than cold air generators powered by electricity, such as air conditioners.

The applications include:

cooling of tools during machining to increase their life cycle and reduce, or even replace, the use of emulsions which are expensive to purchase and dispose of due to pollution

cooling of resins or hot glue to speed up the drying process and, thus, the overall rate of production

the cooling of components in electrical panels

The VR Series coolers (included here) on offer deliver high performance in all of the above-mentioned applications and much more. In addition to excellent performance in comparison to other products on the market, they have been designed both to be offered in custom configurations tailored specifically to customer needs (one of Simian Project’s main strengths is this service) and to be combined in a patented system with the AM Series air flow amplifiers. The latter system, applied both in chip removal to combine cooling with the removal of particles generated by machining and to the cooling of electrical panels for hot air removal and the generation of convection currents that increase cooling efficiency, produces extremely interesting results that have already found their way into different companies, solving problems that had never been tackled before in a decisive manner.

OVER 50 YEARS’ EXPERIENCE

We have been operating in the industrial automation field since 1965, distributing components for the pneumatic, hydraulic, vacuum and fluid control sectors.